Actuating lever

ABSTRACT

An actuating lever ( 1 ), in particular for adjusting a vehicle seat, has an axle receptacle ( 2 ), an articulation device ( 4 ) for force delivery and a grip piece ( 3 ). The actuating lever ( 1 ) is manufactured in one piece from plastic, a core ( 5 ) which comprises the axle receptacle ( 2 ) and the articulation device ( 4 ) is manufactured from a material having higher strength than the grip piece ( 3 ).

CROSS REFERENCE TO RELATED APPLICATIONS

The present application incorporates by reference and claims priority tothe following application: German Patent Application Serial Number 10211 662.8, filed Mar. 15, 2002, and International Patent ApplicationSerial Number PCT/EP03/02694, filed Mar. 14, 2003.

BACKGROUND OF THE INVENTION

The invention relates to an actuating lever, in particular for adjustinga vehicle seat, with an axle receptacle, with an articulation device forforce delivery and with a grip piece.

Generic actuating levers are known from practice and serve, for examplefor releasing the locking device of a seat length or seat heightadjuster. In this case, when the grip piece is pulled or pressed, thelever pivots about an axis of rotation and displaces an articulationdevice for force delivery, located in the lever, in particular a lugsuitable for receiving a bolt. This lug can be in interaction with thelocking device via a linkage or a Bowden cable, so that displacement ofthe articulation device brought about by the operation of the grip pieceis transmitted to the locking device and releases the latter.

Highly loaded actuating levers of this type are conventionally producedeither from a pressed and stamped steel sheet, if appropriate inconjunction with a grip piece bent from round material and welded on, orby means of metal diecasting.

The first-mentioned levers are extremely cost-effective to manufacture,but may not satisfy stringent demands in terms of the configurationpossibilities. Although it is possible, in a diecasting method, toproduce high-strength actuating levers of complex geometry which can beadditionally chromium-plated for a further improvement in visualappearance, these levers are nevertheless relatively heavy and aretherefore inclined, because of their mass inertia, in an accidentsituation to release the adjustment device unintentionally due to theacceleration forces acting on them. It is therefore necessary always toact upon these actuating levers with a relatively high springforcedirected opposite to the release direction. This makes intended releasemore difficult and, furthermore, increases the cost of the levermechanism.

The object on which the invention is based is to provide a lightweight,high-strength actuating lever which meets high requirements as todimensional configuration and surface quality.

SUMMARY OF THE INVENTION

The object is achieved, according to the invention, in that theactuating lever is manufactured in one piece from plastic, a core whichcomprises the axle receptacle and the articulation device beingmanufactured from a material of higher strength than the grip piece, thelength of the grip piece preferably being greater than the distancebetween the axle receptacle and the articulation device.

A visually especially sophisticated actuating lever can be produced inthat the material of the grip piece essentially encases the coreconsisting of higher-strength material. The core is advantageouslymanufactured from a fiber-reinforced plastic, in particular from aglass-fiber-reinforced styrene-acrylonitrile (SAN), while the materialof the grip piece consists of a polycarbonate compound, in particular ofan unreinforced polycarbonate acrylobutadiene styrene (PC-ABS) compound.The last-mentioned material can be processed with high surface quality,so that it can be covered with a high-grade chromium layer.

The production of the actuating lever according to the invention ispreferably carried out by injection molding, in particular by themonosandwich method. In this, two melts are first layered in successionin a common worm cylinder, the second melt being plasticized via asecondary extruder into the worm cylinder of the main assembly. Theinjection operation then takes place in a similar way to conventionalinjection molding with only a single stroke. The sandwich structuresoccur due to the flow properties of the axially layered melts in theworm cylinder. The material injected first is in this case laid onto thewall of the die cavity, while the material injected subsequently formsthe core.

BRIEF DESCRIPTION OF THE FIGURE

The FIGURE illustrates diagrammatically, by way of example, alongitudinal section through an embodiment of the invention.

DESCRIPTION

The actuating lever 1 is provided with an axle receptacle 2, from whicha first lever arm forming a grip piece 3 extends forward and a secondlever arm equipped with an articulation device 4 in the form of a lugextends downward at right angles to the first lever arm. The length ofthe grip piece 3 is in this case considerably greater than the distancebetween the axle receptacle 2 and the articulation device 4, so that theforces introduced into the grip piece at the end face are intensified.The region between the receptacle axle 2 and the articulation device 4is therefore subjected to a substantially higher load in mechanicalterms than the remaining part of the actuating lever 1.

In order to meet these requirements, the core 5 connecting the axlereceptacle 2 and the articulation device 4 consists of a glass-fiberreinforced styrene acrylonitrile (SAN) which has a glass fiber fractionof at least 20%, but preferably about 35%. Even under load at acomparatively high temperature of 80% C, this material possessesconsiderable strength, but it has only an unsatisfactory surface.

The core 5 is therefore provided with a casing 6 made from the materialof the grip piece 3 which consists of an acrylobutadiene styrene(PC-ABS) compound. This material has sufficient strength, in terms ofthe forces occurring in the grip piece 3, even under relatively hightemperatures, but, because of its high surface quality, allows theapplication of a chromium layer 7 which completely surrounds theactuating lever. Experience shows that, even slight unevenness of thebase, for example structures of a fiber reinforcement, stand out in thechromium layer 7. Furthermore, manufacture by the monosandwich methodavoids the situation where the die cavity is opened during manufacture.The surface quality of the actuating lever is therefore sufficientlygood, even in the region of the parting edges, so that remachining isnot necessary.

The actuating lever according to the invention can advantageously beused not only for releasing a seat adjustment, but, furthermore, also inall fields of use wherever a low weight in conjunction with ahigh-quality visual appearance is required, particularly in theequipping of vehicle interiors. Thus, an actuating lever of this typemay also be used as an interior-side door opener or for the opening ofglove compartments or the like.

1. An actuating lever, in particular for adjusting a vehicle seat,comprising: an axle receptacle with an articulation device for forcedelivery; and a grip piece manufactured in one piece from plastic havinga core which comprises the axle receptacle and wherein the articulationdevice is manufactured from a material of higher strength than the grippiece.
 2. The actuating lever as claimed in claim 1, wherein the lengthof the grip piece is greater than the distance between the axlereceptacle and the articulation device.
 3. The actuating lever asclaimed in claim 2, wherein the material of the grip piece substantiallyencases the core, the core consisting of a relatively higher-strengthmaterial.
 4. The actuating lever as claimed in claim 3, wherein the corecomprises a fiber-reinforced plastic including a glass-fiber-reinforcedstyrene acrylonitrile.
 5. The actuating lever as claimed in claim 3,wherein the material of the grip piece comprises a polycarbonatecompound including an unreinforced polycarbonate acrylobutadiene styrenecompound.
 6. The actuating lever as claimed in claim 5, wherein thematerial of the grip piece is covered with a chromium layer.
 7. Theactuating lever as claimed in claim 6, produced by injection moldingutilizing a monosandwich method.